Quick answerA roof diagram is a scaled top-down line drawing of the roof plan: solid lines mark eaves, rakes, hips, and ridges; diagonal lines running into a corner mark valleys; each facet carries a number and a pitch label, and a legend totals the lengths by line type plus the area and pitch mix. To check it against an estimate, match the facet numbers and totals on the diagram to the facets and line items inside the Xactimate® or Symbility® sketch, since both are built from the same measured outline.

What the diagram is actually showing you

The diagram is a plan view of the roof, meaning you are looking straight down at it, not at a photo or a rendered 3D model. Every line on the page is an edge of the roof: where a slope meets a gutter, where two slopes meet each other, or where a slope ends at a gable wall.

Each flat plane of the roof is a facet. A simple gable roof has two facets. A hip roof with dormers can have a dozen or more. The diagram numbers every facet so it can be referenced elsewhere in the report and in the estimate, and each facet carries its own pitch label because two facets on the same roof do not have to share a slope.

Line types and what each edge means

Providers vary slightly in line weight and color, but the roof geometry the lines describe is standard. Learn the edge types once and you can read any provider's diagram.

Line typeWhere it sitsWhat it represents
EaveBottom edge of a slope, over the gutter lineHorizontal drainage edge; drip edge and gutter attach here
RakeSloped edge along a gable endRoof edge that runs up the slope instead of level with the ground
RidgeTop horizontal line where two slopes meetHighest point of the roof; ridge cap and ridge vent run along it
HipDiagonal line running from a ridge down to an outside cornerTwo slopes meeting at an outside corner; hip cap runs along it
ValleyDiagonal line running down into an inside cornerTwo slopes meeting at an inside corner where water concentrates
Wall or step-flashing lineWhere a roof plane meets a vertical wall, dormer, or chimneyFlashing transition, usually shown as a dashed or lighter line

Symbols and labels on each facet

Beyond the outline, a diagram carries a handful of standard labels that tell you the facet's size, slope, and orientation without you needing to scale anything by hand.

  • Facet number: a small identifier (F1, F2, F3...) placed on each plane so it can be referenced in the legend and in the estimate.
  • Pitch label: a slope callout like 6/12 or 8/12 printed on or near the facet.
  • Slope arrow: a small arrow showing the downhill direction of that facet.
  • Dimension lines: straight lines with tick marks and a number, giving the measured length of a specific edge.
  • North arrow: a single arrow, usually in a corner, orienting the plan to the property.
  • Area or square footage callout: a number printed on or near the facet giving that facet's measured area, sometimes shown alongside the pitch.

The legend: how the totals are built

The legend is a small table, usually in a corner of the page, that sums every line type across the whole roof: total eave length, total rake, total ridge, total hip, total valley, and total roof area, often broken out by predominant pitch. This is the section to check first when you are validating a diagram against a scope, because it is where a missing facet or an unmeasured dormer will show up as a total that does not match what you counted on the drawing.

  • Facet count on the drawing matches the facet count in the legend

    A facet drawn but not numbered, or numbered but not drawn, means the totals below it are wrong.

  • Predominant pitch on the legend matches what most facets show

    The predominant pitch drives the waste and labor pitch multipliers used in the estimate.

  • Eave, rake, hip, ridge, and valley totals add up to lengths you can spot-check on the drawing

    These totals drive drip edge, ridge cap, hip and ridge, and valley metal line items directly.

  • Total area divided by 100 gives a squares figure that matches what is scoped

    One roofing square is 100 square feet; a mismatch here usually traces back to an excluded or duplicated facet.

Pitch multiplier: the math behind the area label

Every facet's area comes from its flat footprint multiplied by a pitch multiplier, because a sloped plane covers more material than its footprint on the ground. The formula is: multiplier = square root of (rise squared plus run squared), divided by run. Facet area = footprint area times that multiplier.

PitchMultiplier1,000 sq ft footprint becomes
4/121.0541,054 sq ft
6/121.1181,118 sq ft
8/121.2021,202 sq ft
12/121.4141,414 sq ft

When a facet's pitch label and its area do not scale the way this table predicts, check whether the footprint was measured correctly before assuming the pitch is wrong.

How the diagram maps to the Xactimate® sketch

The diagram and the sketch inside the estimate come from the same measured roof outline, so the facet numbers, edge lengths, and pitches on the page should line up one-for-one with the facets in the sketch tool once the file is imported. A report delivered as an ESX file is built to be brought in via the sketch import option in your estimating platform; exact menu paths vary by version, so verify the current steps in your build against the vendor's own documentation.

Once imported, treat the printed diagram as your check copy. Walk facet by facet: does F1 on the page match F1 in the sketch for pitch and area, do the eave and rake totals in the legend match what the sketch reports, and does the roof's total square footage match the squares used to price the line items. Any gap is worth resolving before the estimate goes out, not after.

  1. Import the file

    Bring the ESX (Xactimate®) or XML (Symbility®) into your estimating platform using the sketch import option; menus vary by version, so confirm the current path in your build.

  2. Match facet numbers

    Confirm each facet number on the printed diagram appears once in the imported sketch, with the same pitch label.

  3. Check the edge totals

    Compare the legend's eave, rake, hip, ridge, and valley totals to the lengths the sketch is using to drive drip edge, ridge cap, and valley line items.

  4. Reconcile the area

    Confirm total squares in the sketch match total area on the diagram divided by 100.

  5. Flag and correct

    If a facet, pitch, or total does not match, correct it in the sketch or request a revision on the report before the estimate is finalized.

Where to order the underlying report

If you are working from an address rather than a diagram someone else supplied, Sketch My Roof roof measurement reports deliver the diagram as ESX, XML, or PDF, so the same facet numbers and legend totals discussed above are already formatted for the tool you plan to use. For Verisk™ desks working inside Xactimate®, orders can route through Xactimate® Integration.

Frequently Asked Questions

What is the difference between a hip line and a valley line on a roof diagram?
A hip runs diagonally from the ridge down to an outside corner, where two slopes meet at a corner that points away from the building. A valley runs diagonally down into an inside corner, where two slopes meet at a corner that points into the building and collects water. Both are drawn as diagonal lines, so check whether the corner is inside or outside the roof's footprint to tell them apart.
Why does each facet have its own pitch label instead of one pitch for the whole roof?
Roofs with dormers, additions, or mixed rooflines commonly have facets at different slopes. Labeling pitch per facet lets the area calculation for each plane use the correct multiplier, and lets the legend report a predominant pitch across the whole roof separately from any facet that differs from it.
What should the legend totals equal when I check them against the drawing?
The legend's eave, rake, hip, ridge, and valley figures should each equal the sum of the matching line segments you can count on the drawing itself, and the total area divided by 100 should equal the squares figure used in the estimate.
Do I need special software to read a roof diagram, or just to import it?
You can read a printed or PDF diagram with no software at all; the symbols and legend are meant to be readable on paper. Importing the underlying file into a sketch tool is only needed when you want the facets to become live, editable line items inside an estimate.

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